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Open Research Positions
Graduate Student Supervision
Doctoral Student Supervision (Jan 2008 - May 2021)
Background: Weakness or damage to the pelvic floor muscles results in pelvicorgan prolapse (POP), which affects 50% of women >50 years old. Posture and gravityimpact organ position and symptom severity. Current limitations of clinical examinationand restriction to imaging in the supine position impact accurate diagnosis and diseasestaging. Open upright magnetic resonance imaging (MRO), allows images of patientssitting, standing, and supine. In this dissertation it is hypothesized that MRO images willallow improved detection of the presence and extent of prolapse.Methods: A Paramed Medical Systems 0.5 T upright Open MRI scanner (MRO)was used to obtain axial and sagittal T2-weighted pelvic scans in women when supine,sitting, and standing. Symptomatic women with POP and asymptomatic controls werestudied. The protocol developed obtains good quality images efficiently in all threepositions. Validated reference lines were used to identify where POP was present in thesame patient in different positions and to grade its severity. A manual segmentationmethodology was developed using Analyze 12.0 software to construct 3D models of thefemale pelvis from 2D images to enhance the visualization of complex pelvic anatomy.Results: Forty women (20 with POP and 20 asymptomatic controls) werestudied. Detection of POP in standing versus supine images in symptomatic womenwas 50% vs. 5% for cystocele and 35% vs. 25% for vaginal prolapse, indicatingimproved visualization of gravity-dependent POP with MRO standing imaging. Imagecomparison indicated that the extent of prolapse is best evaluated in the standingposition using the pubococcygeal reference line. These images better identifydownward movement in the anterior and posterior compartments. No appreciablebenefit was afforded by seated images.Conclusion: The findings support the hypothesis that MRO imaging of POPpatients is relevant to improving the detection and quantification of POP. The MROprotocol developed for standing images in women with POP demonstrated feasibilityallowing supine, sitting, and standing imaging of changes in pelvic floor anatomy inupright positioning. When compared with supine images, standing images better identifythe presence and extent of POP. 3D image modeling allows more comprehensivevisualization of complex female pelvic anatomy.
Master's Student Supervision (2010 - 2020)
Introduction and Objective: Near infrared spectroscopy (NIRS) is a noninvasive method of measuring oxygen recovery kinetics in skeletal muscle. NIRS detects changes in oxygenated (O₂Hb) and deoxygenated (HHb) hemoglobin in response to exercise, to provide interpretation of muscular capacity to restore incurred oxygen debt. Assessment of pelvic floor muscle (PFM) function is central to managing urinary incontinence (UI) and lower urinary tract symptoms (LUTS) but currently lacks oxygen kinetic parameters. This project aims to develop a NIRS probe that measures oxygen kinetics of bilateral PFM in females with UI/LUTS (cases) related to altered pelvic innervation compared to continent controls.Methods: A transvaginal NIRS prototype to detect bilateral PFM was developed. The vaginal NIRS probe monitored female volunteers during sustained PFM contraction (SMVC). O₂Hb, HHb and HbDiff (O₂Hb-HHb) allowed measurement of oxygen kinetics unique to bilateral PFM. Oxygen recovery kinetics determined by HbDiff half recovery time (½RT). PFM manometry assessed SMVC peak and average cmH₂O. Home-based 8-week PFM therapy (PFMT) intervention was performed by both participant groups and an exercise diary measured adherence, determined as total percentage of volume and frequency.Results: Observational NIRS findings demonstrated typical hemodynamic and ½RT responses in controls. Case group demonstrated atypical findings consistent with impaired muscle function. NIRS found quicker ½RT for controls (7.87 vs 38.03 seconds, p 0.01). Manometer detected greater PFM strength and endurance in controls (SMVC peak 35 vs 13 cmH2O, p